Field-amplified sample injection-micellar electrokinetic capillary chromatography for the analysis of bisphenol A, bisphenol F, and their diglycidyl ethers and derivatives in canned soft drinks

Abstract

Conditions were established for the separation and analysis of Bisphenol A (BPA), Bisphenol F (BPF), and their diglycidyl ethers, by micellar electrokinetic capillary chromatography (MECC). Good resolution was obtained for all compounds, although in order to achieve the separation of ortho-ortho, ortho-para, and para-para isomers of Bisphenol F diglycidyl ether (BFDGE), BFDGE¿2H2O and BFDGE¿2HCl, it was necessary to use a 25 µm I.D. fused-silica capillary. To increase sensitivity, a field amplified sample injection (FASI)-MECC method was developed using 10 mM sodium dodecyl sulfate (SDS) solution as injection matrix and a 75 µm I.D. fused-silica capillary. Instrumental quality parameters such as limits of detection (0.999), and run-to-run and day-to-day precisions (relative standard deviations (RSD) values lower than 12.5%) were determined. Finally, the suitability of the FASI-MECC method for the analysis of BPA, BPF and their diglycidyl ethers in canned soft-drinks was evaluated. Quantitation was performed by matrix-matched calibration using a plastic-bottled isotonic drink as matrix. The results showed that FASI-MECC is an economic method for the screening and quantitation of these kinds of compounds in soft-drink beverages, with no loss of reproducibility, and effective at concentrations lower than the specific migration level (SML) values established by the European Union.